Problem in analog operation of Athearn Challenger

I have been trying to get buttons 3, 5 and STP to work when the engine is stopped at idle using the remote. Yet those same buttons function for the operation of the loco once its’ moving. Athearn says I should be able to access three sounds with those buttons when at idle avccording to the manual. I am doing something wrong or is my new Loco need to be repaited. Any help will be greatly appreciated. Happy Holidays!!!

The “remote” [xx(]in DC operation is one of the reasons I switched to DCC!! E-mail Athern - they were helpful to me & exchanged the remote for a new unit - it is still less than perfect - go DCC!![8D]